drivers/rtc/rtc-s3c.c: replace #include header files from asm/* to linux/*

Fixes the following checkpatch warnings:

  WARNING: Use #include <linux/uaccess.h> instead of <asm/uaccess.h>
  WARNING: Use #include <linux/io.h> instead of <asm/io.h>

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/rtc-r9701.c: check that r9701_set_datetime() succeeded

When the driver detects that the clock time is invalid, it attempts to
write a sane time into the hardware.  We curently assume that everything
is OK if those writes succeeded.  But it is better to re-read the time
from the hardware to ensure that the new settings got there OK.

Cc: Devendra Naga <devendra.aaru@gmail.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Anatolij Gustschin <agust@denx.de>
Cc: Andreas Dumberger <andreas.dumberger@tqs.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/rtc-r9701.c: avoid second call to rtc_valid_tm()

r9701_get_datetime() calls rtc_valid_tm() and returns the value returned
by rtc_valid_tm(), which can be used in the `if', so calling
rtc_valid_tm() a second time is not required.

Signed-off-by: Devendra Naga <devendra.aaru@gmail.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Anatolij Gustschin <agust@denx.de>
Cc: Andreas Dumberger <andreas.dumberger@tqs.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/rtc-ab8500.c: remove fix for AB8500 ED version

AB8500 ED (Early Drop) is no longer supported by the kernel.

Signed-off-by: Bengt Jonsson <bengt.g.jonsson@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/rtc-ab8500.c: use UIE emulation

RTC: Fix to correct improper implementation of clock update irq
(RTC_UIE) and enable UIE Emulation.

[akpm@linux-foundation.org: checkpatch fixes]
Signed-off-by: Ramesh Chandrasekaran <ramesh.chandrasekaran@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

rtc: pl031: fix up IRQ flags

The pl031 interrupt is shared between the timer part and the clockwatch
part of the same HW block on the ux500, so mark it IRQF_SHARED on this
variant.

This patch also adds the IRQF_NO_SUSPEND flag to the rtc irq on all
variants as we don't want this pretty important IRQ to be disabled in
suspend.

Signed-off-by: Mattias Wallin <mattias.wallin@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Rickard Andersson <rickard.andersson@stericsson.com>
Reviewed-by: Jonas Aberg <jonas.aberg@stericsson.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

rtc: pl031: use per-vendor variables for special init

Instead of hard-checking for certain vendor codes, follow the pattern of
other AMBA (PrimeCell) drivers and use variables in the vendor data.
Get rid of the locally cached vendor and hardware revision since we
already have the nice vendor data variable in the state.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

rtc: pl031: encapsulate per-vendor ops

Move the per-vendor operations for this RTC into a encapsulating struct so
we can have more per-vendor variables than just the ops.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/rtc-coh901331.c: use devm allocation

Allocate memory, region, remap and irq for device state using devm_*
helpers to simplify memory accounting.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/rtc-coh901331.c: use clk_prepare/unprepare

Make sure we prepare/unprepare the clock for the COH901331 RTC driver as
is required by the clk API especially if you use common clock.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/message/i2o/i2o_config.c: bound allocation

Fix a case where users can try to allocate arbitarily large amounts of
memory. 64K is overkill for a config request so apply an upper bound.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/message/i2o/i2o_proc.c: the pointer returned from chtostr() points to an array which is no longer valid

...  when being used in the calling function.  Although it may work, the
behavior is undefined.  Detected by cppcheck.

Signed-off-by: Kamil Dudka <kdudka@redhat.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

lib/crc32.c: fix unused variables warnings

Variables t4, t5, t6 and t7 are only used when CRC_LE_BITS != 32.  Fix
the following compilation warnings:

  lib/crc32.c: In function 'crc32_body':
  lib/crc32.c:77:55: warning: unused variable 't7'
  lib/crc32.c:77:41: warning: unused variable 't6'
  lib/crc32.c:77:27: warning: unused variable 't5'
  lib/crc32.c:77:13: warning: unused variable 't4'

Signed-off-by: Thiago Rafael Becker <trbecker@trbecker.org>
Cc: "Darrick J. Wong" <djwong@us.ibm.com>
Cc: Bob Pearson <rpearson@systemfabricworks.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

checkpatch: add checks for do {} while (0) macro misuses

These types of macros should not be used for either a single statement
nor should the macro end with a semi-colon.

Add tests for these conditions.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

checkpatch: Add acheck for use of sizeof without parenthesis

Kernel style uses parenthesis around sizeof.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

checkpatch: check usleep_range() arguments

usleep_range() shouldn't use the same args for min and max.

Report it when it happens and when both args are decimal and min > max.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Yuval Mintz <yuvalmin@broadcom.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

checkpatch: test for non-standard signatures

Warn on non-standard signature styles.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

checkpatch: Update alignment check

Parenthesis alignment doesn't correctly check an existing line after an
inserted or modified line with an open parenthesis.

Fix it.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

firmware_map: make firmware_map_add_early() argument consistent with firmware_map_add_hotplug()

There are two ways to create /sys/firmware/memmap/X sysfs:

  - firmware_map_add_early
    When the system starts, it is calledd from e820_reserve_resources()
  - firmware_map_add_hotplug
    When the memory is hot plugged, it is called from add_memory()

But these functions are called without unifying value of end argument as
below:

  - end argument of firmware_map_add_early()   : start + size - 1
  - end argument of firmware_map_add_hogplug() : start + size

The patch unifies them to "start + size".  Even if applying the patch,
/sys/firmware/memmap/X/end file content does not change.

[akpm@linux-foundation.org: clarify comments]
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Reviewed-by: Dave Hansen <dave@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

spinlock_debug: print offset in addition to symbol name

If there are two spinlocks embedded in a structure that kallsyms knows
about and one of the spinlocks locks up we will print the name of the
containing structure instead of the address of the lock.  This is quite
bad, so let's use %pS instead of %ps so we get an offset in addition to
the symbol so we can determine which particular lock is having problems.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

atomic64_test: simplify the #ifdef for atomic64_dec_if_positive() test

Introduce CONFIG_ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE and use this instead
of the multitude of #if defined() checks in atomic64_test.c

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ext4: use memweight()

Convert ext4_count_free() to use memweight() instead of table lookup
based counting clear bits implementation.  This change only affects the
code segments enabled by EXT4FS_DEBUG.

Note that this memweight() call can't be replaced with a single
bitmap_weight() call, although the pointer to the memory area is aligned
to long-word boundary.  Because the size of the memory area may not be a
multiple of BITS_PER_LONG, then it returns wrong value on big-endian
architecture.

This also includes the following change.

- Remove unnecessary map == NULL check in ext4_count_free() which
  always takes non-null pointer as the memory area.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ext3: use memweight()

Convert ext3_count_free() to use memweight() instead of table lookup
based counting clear bits implementation.  This change only affects the
code segments enabled by EXT3FS_DEBUG.

Note that this memweight() call can't be replaced with a single
bitmap_weight() call, although the pointer to the memory area is aligned
to long-word boundary.  Because the size of the memory area may not be a
multiple of BITS_PER_LONG, then it returns wrong value on big-endian
architecture.

This also includes the following changes.

- Remove unnecessary map == NULL check in ext3_count_free() which
  always takes non-null pointer as the memory area.

- Fix printk format warning that only reveals with EXT3FS_DEBUG.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Acked-by: Jan Kara <jack@suse.cz>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ext2: use memweight()

Convert ext2_count_free() to use memweight() instead of table lookup
based counting clear bits implementation.  This change only affects the
code segments enabled by EXT2FS_DEBUG.

Note that this memweight() call can't be replaced with a single
bitmap_weight() call, although the pointer to the memory area is aligned
to long-word boundary.  Because the size of the memory area may not be a
multiple of BITS_PER_LONG, then it returns wrong value on big-endian
architecture.

This also includes the following changes.

- Remove unnecessary map == NULL check in ext2_count_free() which
  always takes non-null pointer as the memory area.

- Fix printk format warning that only reveals with EXT2FS_DEBUG.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ocfs2: use memweight()

Use memweight to count the total number of bits set in memory area.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

video/uvc: use memweight()

Use memweight() to count the total number of bits set in memory area.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

affs: use memweight()

Use memweight() to count the total number of bits set in memory area.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

dm: use memweight()

Use memweight() to count the total number of bits set in memory area.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Alasdair Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

qnx4fs: use memweight()

Use memweight() to count the total number of bits clear in memory area.

Note that this memweight() call can't be replaced with a single
bitmap_weight() call, although the pointer to the memory area is aligned
to long-word boundary.  Because the size of the memory area may not be a
multiple of BITS_PER_LONG, then it returns wrong value on big-endian
architecture.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Acked-by: Anders Larsen <al@alarsen.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

string: introduce memweight()

memweight() is the function that counts the total number of bits set in
memory area.  Unlike bitmap_weight(), memweight() takes pointer and size
in bytes to specify a memory area which does not need to be aligned to
long-word boundary.

[akpm@linux-foundation.org: rename `w' to `ret']
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Anders Larsen <al@alarsen.net>
Cc: Alasdair Kergon <agk@redhat.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Jan Kara <jack@suse.cz>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Matthew Wilcox <matthew@wil.cx>
Cc: Mauro Carvalho Chehab <mchehab@infradead.org>
Cc: Tony Luck <tony.luck@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

backlight: move lp855x header into platform_data directory

The lp855x header is used only in the platform side, so it can be moved
into platform_data directory

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Bryan Wu <bryan.wu@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

backlight: move register definitions from header to source

ROM boundary definitions do not need to be exported because these are
used only internally in the lp855x driver.

And few code cosmetic changes

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Bryan Wu <bryan.wu@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

backlight: l4f00242t03: export and use devm_gpio_request_one()

The devm_ functions allocate memory that is released when a driver
detaches.  This patch uses devm_gpio_request_one() for these functions.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Cc: Alberto Panizzo <alberto@amarulasolutions.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

backlight: corgi_lcd: use devm_gpio_request()

The devm_ functions allocate memory that is released when a driver
detaches.  This patch uses devm_gpio_request() for these functions.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Cc: Eric Miao <eric.y.miao@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

backlight: lms283gf05: use devm_gpio_request()

The devm_ functions allocate memory that is released when a driver
detaches.  This patch uses devm_gpio_request() for these functions.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Marek Vasut <marek.vasut@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

backlight: tosa_bl: use devm_gpio_request()

The devm_ functions allocate memory that is released when a driver
detaches.  This patch uses devm_gpio_request() for these functions.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Cc: Dmitry Baryshkov <dbaryshkov@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

backlight: tosa_lcd: use devm_gpio_request()

The devm_ functions allocate memory that is released when a driver
detaches.  This patch uses devm_gpio_request() for these functions.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Cc: Dmitry Baryshkov <dbaryshkov@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

backlight: ot200_bl: use devm_gpio_request()

The devm_ functions allocate memory that is released when a driver
detaches.  This patch uses devm_gpio_request() for these functions.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Christian Gmeiner <christian.gmeiner@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

backlight: atmel-pwm-bl: use devm_gpio_request()

The devm_ functions allocate memory that is released when a driver
detaches.  This patch uses devm_gpio_request() for these functions.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/video/backlight/lm3533_bl.c: use devm_ functions

The devm_ functions allocate memory that is released when a driver
detaches.  This patch uses devm_kzalloc of these functions.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Johan Hovold <jhovold@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/video/backlight/ot200_bl.c: use devm_ functions

The devm_ functions allocate memory that is released when a driver
detaches. This patch uses devm_kzalloc of these functions

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Cc: Christian Gmeiner <christian.gmeiner@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/video/backlight/atmel-pwm-bl.c: use devm_ functions

The devm_ functions allocate memory that is released when a driver
detaches.  This patch uses devm_kzalloc of these functions.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

MAINTAINERS: update EXYNOS DP DRIVER F: patterns

Add patterns for Exynos DP header to MAINTAINERS file.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

vsprintf: add support of '%*ph[CDN]'

There are many places in the kernel where the drivers print small buffers
as a hex string.  This patch adds a support of the variable width buffer
to print it as a hex string with a delimiter.  The idea came from Pavel
Roskin here: http://www.digipedia.pl/usenet/thread/18835/17449/

Sample output of
pr_info("buf[%d:%d] %*phC\n", from, len, len, &buf[from]);
could be look like this:
[ 0.726130] buf[51:8] e8:16:b6:ef:e3:74:45:6e
[ 0.750736] buf[59:15] 31:81:b8:3f:35:49:06:ae:df:32:06:05:4a:af:55
[ 0.757602] buf[17:5] ac:16:d5:2c:ef

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

lib/vsprintf.c: kptr_restrict: fix pK-error in SysRq show-all-timers(Q)

When using ALT+SysRq+Q all the pointers are replaced with "pK-error" like
this:

[23153.208033]   .base:               pK-error

with echo h > /proc/sysrq-trigger it works:

[23107.776363]   .base:       ffff88023e60d540

The intent behind this behavior was to return "pK-error" in cases where
the %pK format specifier was used in interrupt context, because the
CAP_SYSLOG check wouldn't be meaningful.  Clearly this should only apply
when kptr_restrict is actually enabled though.

Reported-by: Stevie Trujillo <stevie.trujillo@gmail.com>
Signed-off-by: Dan Rosenberg <dan.j.rosenberg@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

lib/vsprintf.c: remind people to update Documentation/printk-formats.txt when adding printk formats

Cc: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

vsprintf: add %pMR for Bluetooth MAC address

Bluetooth uses mostly LE byte order which is reversed for visual
interpretation.  Currently in Bluetooth in use unsafe batostr function.

This is a slightly modified version of Joe's patch (sent Sat, Dec 4,
2010).

Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Cc: Joe Perches <joe@perches.com>
Cc: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

printk: remove the now unnecessary "C" annotation for KERN_CONT

Now that all KERN_<LEVEL> uses are prefixed with ASCII SOH, there is no
need for a KERN_CONT.  Keep it backward compatible by adding #define
KERN_CONT ""

Reduces kernel image size a thousand bytes.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

printk: only look for prefix levels in kernel messages

vprintk_emit() prefix parsing should only be done for internal kernel
messages.  This allows existing behavior to be kept in all cases.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Kay Sievers <kay@vrfy.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

printk: convert the format for KERN_<LEVEL> to a 2 byte pattern

Instead of "<.>", use an ASCII SOH for the KERN_<LEVEL> prefix initiator.

This saves 1 byte per printk, thousands of bytes in a normal kernel.

No output changes are produced as vprintk_emit converts these uses to
"<.>".

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

sound: use printk_get_level and printk_skip_level

Make the output logging routine independent of the KERN_<LEVEL> style.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

btrfs: use printk_get_level and printk_skip_level, add __printf, fix fallout

Use the generic printk_get_level() to search a message for a kern_level.

Add __printf to verify format and arguments.  Fix a few messages that
had mismatches in format and arguments.  Add #ifdef CONFIG_PRINTK blocks
to shrink the object size a bit when not using printk.

[akpm@linux-foundation.org: whitespace tweak]
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Chris Mason <chris.mason@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch: remove direct definitions of KERN_<LEVEL> uses

Add #include <linux/kern_levels.h> so that the #define KERN_<LEVEL> macros
don't have to be duplicated.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Kay Sievers <kay@vrfy.org>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

printk: add kern_levels.h to make KERN_<LEVEL> available for asm use

Separate the printk.h file into 2 pieces so the definitions can be used in
asm files.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

printk: add generic functions to find KERN_<LEVEL> headers

The current form of a KERN_<LEVEL> is "<.>".

Add printk_get_level and printk_skip_level functions to handle these
formats.

These functions centralize tests of KERN_<LEVEL> so a future modification
can change the KERN_<LEVEL> style and shorten the number of bytes consumed
by these headers.

[akpm@linux-foundation.org: fix build error and warning]
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Wu Fengguang <wfg@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kmsg: /dev/kmsg - properly return possible copy_from_user() failure

Reported-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Kay Sievers <kay@vrfy.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/misc/ti-st/st_core.c: missing NULL check

Addresses https://bugzilla.kernel.org/show_bug.cgi?44431

Reported-by: <rucsoftsec@gmail.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Cc: Pavan Savoy <pavan_savoy@ti.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kernel/sys.c: avoid argv_free(NULL)

If argv_split() failed, the code will end up calling argv_free(NULL).  Fix
it up and clean things up a bit.

Addresses Coverity report 703573.

Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Serge Hallyn <serge.hallyn@canonical.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: WANG Cong <xiyou.wangcong@gmail.com>
Cc: Alan Cox <alan@linux.intel.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

NMI watchdog: fix for lockup detector breakage on resume

On the suspend/resume path the boot CPU does not go though an
offline->online transition.  This breaks the NMI detector post-resume
since it depends on PMU state that is lost when the system gets
suspended.

Fix this by forcing a CPU offline->online transition for the lockup
detector on the boot CPU during resume.

To provide more context, we enable NMI watchdog on Chrome OS.  We have
seen several reports of systems freezing up completely which indicated
that the NMI watchdog was not firing for some reason.

Debugging further, we found a simple way of repro'ing system freezes --
issuing the command 'tasket 1 sh -c "echo nmilockup > /proc/breakme"'
after the system has been suspended/resumed one or more times.

With this patch in place, the system freeze result in panics, as
expected.

These panics provide a nice stack trace for us to debug the actual issue
causing the freeze.

[akpm@linux-foundation.org: fiddle with code comment]
[akpm@linux-foundation.org: make lockup_detector_bootcpu_resume() conditional on CONFIG_SUSPEND]
[akpm@linux-foundation.org: fix section errors]
Signed-off-by: Sameer Nanda <snanda@chromium.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Mandeep Singh Baines <msb@chromium.org>
Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

panic: fix a possible deadlock in panic()

panic_lock is meant to ensure that panic processing takes place only on
one cpu; if any of the other cpus encounter a panic, they will spin
waiting to be shut down.

However, this causes a regression in this scenario:

1. Cpu 0 encounters a panic and acquires the panic_lock
   and proceeds with the panic processing.
2. There is an interrupt on cpu 0 that also encounters
   an error condition and invokes panic.
3. This second invocation fails to acquire the panic_lock
   and enters the infinite while loop in panic_smp_self_stop.

Thus all panic processing is stopped, and the cpu is stuck for eternity
in the while(1) inside panic_smp_self_stop.

To address this, disable local interrupts with local_irq_disable before
acquiring the panic_lock.  This will prevent interrupt handlers from
executing during the panic processing, thus avoiding this particular
problem.

Signed-off-by: Vikram Mulukutla <markivx@codeaurora.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Cc: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

avr32: fix build error in ATSTK1002 code

Fix the error

  arch/avr32/boards/atstk1000/atstk1002.c:100: error: 'num_partitions' undeclared here (not in a function)

which was introduced by commit 1754aab9bb86 ("mtd: ATMEL, AVR32: inline
nand partition table access ").

Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Cc: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

clk: validate pointer in __clk_disable()

clk_get() returns -ENOENT on error and some careless caller might
dereference it without error checking:

In mxc_rnga_remove():

        struct clk *clk = clk_get(&pdev->dev, "rng");

// ...

        clk_disable(clk);

Since it's insane to audit the lots of existing and future clk users,
let's add a check in the callee to avoid kernel panic and warn about
any buggy user.

Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Viresh Kumar <viresh.kumar@st.com>
Cc: viresh kumar <viresh.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/arm/mach-netx/fb.c: reuse dummy clk routines for CONFIG_HAVE_CLK=n

mach-netx had its own implementation of clk routines like, clk_get{put},
clk_enable{disable}, etc.  And with introduction of following patchset:

  https://lkml.org/lkml/2012/4/24/154

we get compilation error for multiple definition of these routines.

Sascha had following suggestion to deal with it:

  http://www.spinics.net/lists/arm-kernel/msg179369.html

So, remove this code completely.

Signed-off-by: Viresh Kumar <viresh.kumar2@arm.com>
Reported-by: Paul Gortmaker <paul.gortmaker@gmail.com>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

usb/host/r8a66597: remove conditional compilation of clk code

With addition of dummy clk_*() calls for non CONFIG_HAVE_CLK cases in
clk.h, there is no need to have clk code enclosed in #ifdef
CONFIG_HAVE_CLK, #endif macros.

Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Mike Turquette <mturquette@linaro.org>
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: viresh kumar <viresh.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

gadget/r8a66597: remove conditional compilation of clk code

With addition of dummy clk_*() calls for non CONFIG_HAVE_CLK cases in
clk.h, there is no need to have clk code enclosed in #ifdef
CONFIG_HAVE_CLK, #endif macros.

Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Mike Turquette <mturquette@linaro.org>
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: viresh kumar <viresh.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

gadget/m66592: remove conditional compilation of clk code

With addition of dummy clk_*() calls for non CONFIG_HAVE_CLK cases in
clk.h, there is no need to have clk code enclosed in #ifdef
CONFIG_HAVE_CLK, #endif macros.

Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Mike Turquette <mturquette@linaro.org>
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: viresh kumar <viresh.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

net/stmmac: remove conditional compilation of clk code

With addition of dummy clk_*() calls for non CONFIG_HAVE_CLK cases in
clk.h, there is no need to have clk code enclosed in #ifdef
CONFIG_HAVE_CLK, #endif macros.

This also fixes error paths of probe(), as a goto is required in this
patch.

Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Cc: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Acked-by: David S. Miller <davem@davemloft.net>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Mike Turquette <mturquette@linaro.org>
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: viresh kumar <viresh.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

net/c_can: remove conditional compilation of clk code

With addition of dummy clk_*() calls for non CONFIG_HAVE_CLK cases in clk.h,
there is no need to have clk code enclosed in #ifdef CONFIG_HAVE_CLK, #endif
macros.

Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: David S. Miller <davem@davemloft.net>
Cc: Bhupesh Sharma <bhupesh.sharma@st.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Mike Turquette <mturquette@linaro.org>
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: viresh kumar <viresh.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ata/pata_arasan: remove conditional compilation of clk code

With addition of dummy clk_*() calls for non CONFIG_HAVE_CLK cases in
clk.h, there is no need to have clk code enclosed in #ifdef
CONFIG_HAVE_CLK, #endif macros.

Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Cc: Jeff Garzik <jgarzik@redhat.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Mike Turquette <mturquette@linaro.org>
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: viresh kumar <viresh.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

usb/musb: remove conditional compilation of clk code

With addition of dummy clk_*() calls for non CONFIG_HAVE_CLK cases in
clk.h, there is no need to have clk code enclosed in #ifdef
CONFIG_HAVE_CLK, #endif macros.

musb also has these dummy macros defined locally.  Remove them as they
aren't required anymore.

Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Jeff Garzik <jgarzik@redhat.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Mike Turquette <mturquette@linaro.org>
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: viresh kumar <viresh.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

usb/marvell: remove conditional compilation of clk code

With addition of dummy clk_*() calls for non CONFIG_HAVE_CLK cases in
clk.h, there is no need to have clk code enclosed in #ifdef
CONFIG_HAVE_CLK, #endif macros.

Marvell usb also has these dummy macros defined locally.  Remove them as
they aren't required anymore.

Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Mike Turquette <mturquette@linaro.org>
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: viresh kumar <viresh.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

i2c/i2c-pxa: remove conditional compilation of clk code

With addition of dummy clk_*() calls for non CONFIG_HAVE_CLK cases in
clk.h, there is no need to have clk code enclosed in #ifdef
CONFIG_HAVE_CLK, #endif macros.

pxa i2c also has these dummy macros defined locally.  Remove them as they
aren't required anymore.

Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Mike Turquette <mturquette@linaro.org>
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: viresh kumar <viresh.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

clk: remove redundant depends on from drivers/Kconfig

menu "Common Clock Framework" has "depends on COMMON_CLK" and so configs
defined within menu don't require these "depends on COMMON_CLK again".

Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Cc: Wolfram Sang <w.sang@pengutronix.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jeff Garzik <jgarzik@redhat.com>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Bhupesh Sharma <bhupesh.sharma@st.com>
Cc: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Mike Turquette <mturquette@linaro.org>
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: viresh kumar <viresh.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

clk: add non CONFIG_HAVE_CLK routines

Many drivers are shared between architectures that may or may not have
HAVE_CLK selected for them.  To remove compilation errors for them we
enclose clk_*() calls in these drivers within #ifdef CONFIG_HAVE_CLK,
#endif.

This patch removes the need of these CONFIG_HAVE_CLK statements, by
introducing dummy routines when HAVE_CLK is not selected by platforms.
So, definition of these routines will always be available.  These calls
will return error for platforms that don't select HAVE_CLK.

Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Cc: Wolfram Sang <w.sang@pengutronix.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jeff Garzik <jgarzik@redhat.com>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Bhupesh Sharma <bhupesh.sharma@st.com>
Cc: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Mike Turquette <mturquette@linaro.org>
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: viresh kumar <viresh.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

avr32/mm/fault.c: port OOM changes to do_page_fault

Commits d065bd810b6d ("mm: retry page fault when blocking on disk
transfer") and 37b23e0525d3 ("x86,mm: make pagefault killable")
introduced changes into the x86 pagefault handler for making the page
fault handler retryable as well as killable.

These changes reduce the mmap_sem hold time, which is crucial during OOM
killer invocation.

Port these changes to AVR32.

[akpm@linux-foundation.org: fix comment layout]
Signed-off-by: Mohd. Faris <mohdfarisq2010@gmail.com>
Signed-off-by: Kautuk Consul <consul.kautuk@gmail.com>
Acked-by: Havard Skinnemoen <hskinnemoen@gmail.com>
Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

alpha: remove mysterious if zero-ed out includes

There's a small group of odd looking includes in smc37c669.c.  These
includes appear to be if zero-ed out ever since they were added to the
tree (in v2.1.89).  Their purpose is unclear to me.  Perhaps they were
used in someones build system.  Whatever their purpose was, nothing else
uses something comparable.  This entire if zero-ed out block might as well
be removed.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

xtensa/mm/fault.c: port OOM changes to do_page_fault

Commits d065bd810b6d ("mm: retry page fault when blocking on disk
transfer") and 37b23e0525d3 ("x86,mm: make pagefault killable")
introduced changes into the x86 pagefault handler for making the page
fault handler retryable as well as killable.

These changes reduce the mmap_sem hold time, which is crucial during OOM
killer invocation.

Port these changes to xtensa.

Signed-off-by: Kautuk Consul <consul.kautuk@gmail.com>
Acked-by: Chris Zankel <chris@zankel.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

coredump: warn about unsafe suid_dumpable / core_pattern combo

When suid_dumpable=2, detect unsafe core_pattern settings and warn when
they are seen.

Signed-off-by: Kees Cook <keescook@chromium.org>
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Alan Cox <alan@linux.intel.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Doug Ledford <dledford@redhat.com>
Cc: Serge Hallyn <serge.hallyn@canonical.com>
Cc: James Morris <james.l.morris@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs: make dumpable=2 require fully qualified path

When the suid_dumpable sysctl is set to "2", and there is no core dump
pipe defined in the core_pattern sysctl, a local user can cause core files
to be written to root-writable directories, potentially with
user-controlled content.

This means an admin can unknowningly reintroduce a variation of
CVE-2006-2451, allowing local users to gain root privileges.

  $ cat /proc/sys/fs/suid_dumpable
  2
  $ cat /proc/sys/kernel/core_pattern
  core
  $ ulimit -c unlimited
  $ cd /
  $ ls -l core
  ls: cannot access core: No such file or directory
  $ touch core
  touch: cannot touch `core': Permission denied
  $ OHAI="evil-string-here" ping localhost >/dev/null 2>&1 &
  $ pid=$!
  $ sleep 1
  $ kill -SEGV $pid
  $ ls -l core
  -rw------- 1 root kees 458752 Jun 21 11:35 core
  $ sudo strings core | grep evil
  OHAI=evil-string-here

While cron has been fixed to abort reading a file when there is any
parse error, there are still other sensitive directories that will read
any file present and skip unparsable lines.

Instead of introducing a suid_dumpable=3 mode and breaking all users of
mode 2, this only disables the unsafe portion of mode 2 (writing to disk
via relative path).  Most users of mode 2 (e.g.  Chrome OS) already use
a core dump pipe handler, so this change will not break them.  For the
situations where a pipe handler is not defined but mode 2 is still
active, crash dumps will only be written to fully qualified paths.  If a
relative path is defined (e.g.  the default "core" pattern), dump
attempts will trigger a printk yelling about the lack of a fully
qualified path.

Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Alan Cox <alan@linux.intel.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Doug Ledford <dledford@redhat.com>
Cc: Serge Hallyn <serge.hallyn@canonical.com>
Cc: James Morris <james.l.morris@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/xattr.c:getxattr(): improve handling of allocation failures

This allocation can be as large as 64k.

 - Add __GFP_NOWARN so the falied kmalloc() is silent

 - Fall back to vmalloc() if the kmalloc() failed

Signed-off-by: Sasha Levin <levinsasha928@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ntfs: remove references to long gone super operations and unimplemented methods

->delete_inode(), ->write_super_lockfs(), ->unlockfs() are gone so remove
refereces to them in the NTFS code.  Remove unnecessary comments about
unimplemented methods while at it (suggested by Christoph Hellwig).

Noticed while cleaning up the fsfreeze mess.

Signed-off-by: Fernando Luis Vazquez Cao <fernando@oss.ntt.co.jp>
Cc: Anton Altaparmakov <anton@tuxera.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

prctl: remove redunant assignment of "error" to zero

Just setting the "error" to error number is enough on failure and It
doesn't require to set "error" variable to zero in each switch case,
since it was already initialized with zero.  And also removed return 0
in switch case with break statement

Signed-off-by: Sasikantha babu <sasikanth.v19@gmail.com>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Serge E. Hallyn <serge@hallyn.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

pcdp: use early_ioremap/early_iounmap to access pcdp table

efi_setup_pcdp_console() is called during boot to parse the HCDP/PCDP
EFI system table and setup an early console for printk output.  The
routine uses ioremap/iounmap to setup access to the HCDP/PCDP table
information.

The call to ioremap is happening early in the boot process which leads
to a panic on x86_64 systems:

    panic+0x01ca
    do_exit+0x043c
    oops_end+0x00a7
    no_context+0x0119
    __bad_area_nosemaphore+0x0138
    bad_area_nosemaphore+0x000e
    do_page_fault+0x0321
    page_fault+0x0020
    reserve_memtype+0x02a1
    __ioremap_caller+0x0123
    ioremap_nocache+0x0012
    efi_setup_pcdp_console+0x002b
    setup_arch+0x03a9
    start_kernel+0x00d4
    x86_64_start_reservations+0x012c
    x86_64_start_kernel+0x00fe

This replaces the calls to ioremap/iounmap in efi_setup_pcdp_console()
with calls to early_ioremap/early_iounmap which can be called during
early boot.

This patch was tested on an x86_64 prototype system which uses the
HCDP/PCDP table for early console setup.

Signed-off-by: Greg Pearson <greg.pearson@hp.com>
Acked-by: Khalid Aziz <khalid.aziz@hp.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm: fix wrong argument of migrate_huge_pages() in soft_offline_huge_page()

Commit a6bc32b89922 ("mm: compaction: introduce sync-light migration for
use by compaction") changed the declaration of migrate_pages() and
migrate_huge_pages().

But it missed changing the argument of migrate_huge_pages() in
soft_offline_huge_page().  In this case, we should call
migrate_huge_pages() with MIGRATE_SYNC.

Additionally, there is a mismatch between type the of argument and the
function declaration for migrate_pages().

Signed-off-by: Joonsoo Kim <js1304@gmail.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Mel Gorman <mgorman@suse.de>
Acked-by: David Rientjes <rientjes@google.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Merge branch 'i2c-embedded/for-next' of git://git.pengutronix.de/git/wsa/linux

Pull embedded i2c changes from Wolfram Sang:
 "Changes for the "embedded" part of the I2C subsystem:

   - lots of devicetree conversions of drivers (and preparations for
     that)
   - big cleanups for drivers for OMAP, Tegra, Nomadik, Blackfin
   - Rafael's struct dev_pm_ops conversion patches for I2C
   - usual driver cleanups and fixes

  All patches have been in linux-next for an apropriate time and all
  patches touching files outside of i2c-folders should have proper acks
  from the maintainers."

* 'i2c-embedded/for-next' of git://git.pengutronix.de/git/wsa/linux: (60 commits)
  Revert "i2c: tegra: convert normal suspend/resume to *_noirq"
  I2C: MV64XYZ: Add Device Tree support
  i2c: stu300: use devm managed resources
  i2c: i2c-ocores: support for 16bit and 32bit IO
  V4L/DVB: mfd: use reg_shift instead of regstep
  i2c: i2c-ocores: Use reg-shift property
  i2c: i2c-ocores: DT bindings and minor fixes.
  i2c: mv64xxxx: remove EXPERIMENTAL tag
  i2c-s3c2410: Use plain pm_runtime_put()
  i2c: s3c2410: Fix pointer type passed to of_match_node()
  i2c: mxs: Set I2C timing registers for mxs-i2c
  i2c: i2c-bfin-twi: Move blackfin TWI register access Macro to head file.
  i2c: i2c-bfin-twi: Move TWI peripheral pin request array to platform data.
  i2c:i2c-bfin-twi: include twi head file
  i2c:i2c-bfin-twi: TWI fails to restart next transfer in high system load.
  i2c: i2c-bfin-twi: Tighten condition when failing I2C transfer if MEN bit is reset unexpectedly.
  i2c: i2c-bfin-twi: Break dead waiting loop if i2c device misbehaves.
  i2c: i2c-bfin-twi: Improve the patch for bug "Illegal i2c bus lock upon certain transfer scenarios".
  i2c: i2c-bfin-twi: Illegal i2c bus lock upon certain transfer scenarios.
  i2c-mv64xxxx: allow more than one driver instance
  ...

Conflicts:
drivers/i2c/busses/i2c-nomadik.c

Merge git://git./linux/kernel/git/davem/net

Pull networking fixes from David Miller:
 "Several bug fixes, some to new features appearing in this merge
  window, some that have been around for a while.

  I have a short list of known problems that need to be sorted out, but
  all of them can be solved easily during the run up to 3.6-final.

  I'll be offline until Sunday afternoon, but nothing need hold up
  3.6-rc1 and the close of the merge window, networking wise, at this
  point.

  1) Fix interface check in ipv4 TCP early demux, from Eric Dumazet.

  2) Fix a long standing bug in TCP DMA to userspace offload that can
     hang applications using MSG_TRUNC, from Jiri Kosina.

  3) Don't allow TCP_USER_TIMEOUT to be negative, from Hangbin Liu.

  4) Don't use GFP_KERNEL under spinlock in kaweth driver, from Dan
     Carpenter"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net:
  tcp: perform DMA to userspace only if there is a task waiting for it
  Revert "openvswitch: potential NULL deref in sample()"
  ipv4: fix TCP early demux
  net: fix rtnetlink IFF_PROMISC and IFF_ALLMULTI handling
  USB: kaweth.c: use GFP_ATOMIC under spin_lock
  tcp: Add TCP_USER_TIMEOUT negative value check
  bcma: add missing iounmap on error path
  bcma: fix regression in interrupt assignment on mips
  mac80211_hwsim: fix possible race condition in usage of info->control.sta & control.vif

Merge tag 'ext4_for_linus' of git://git./linux/kernel/git/tytso/ext4

Pull ext4 updates from Ted Ts'o:
 "The usual collection of bug fixes and optimizations.  Perhaps of
  greatest note is a speed up for parallel, non-allocating DIO writes,
  since we no longer take the i_mutex lock in that case.

  For bug fixes, we fix an incorrect overhead calculation which caused
  slightly incorrect results for df(1) and statfs(2).  We also fixed
  bugs in the metadata checksum feature."

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (23 commits)
  ext4: undo ext4_calc_metadata_amount if we fail to claim space
  ext4: don't let i_reserved_meta_blocks go negative
  ext4: fix hole punch failure when depth is greater than 0
  ext4: remove unnecessary argument from __ext4_handle_dirty_metadata()
  ext4: weed out ext4_write_super
  ext4: remove unnecessary superblock dirtying
  ext4: convert last user of ext4_mark_super_dirty() to ext4_handle_dirty_super()
  ext4: remove useless marking of superblock dirty
  ext4: fix ext4 mismerge back in January
  ext4: remove dynamic array size in ext4_chksum()
  ext4: remove unused variable in ext4_update_super()
  ext4: make quota as first class supported feature
  ext4: don't take the i_mutex lock when doing DIO overwrites
  ext4: add a new nolock flag in ext4_map_blocks
  ext4: split ext4_file_write into buffered IO and direct IO
  ext4: remove an unused statement in ext4_mb_get_buddy_page_lock()
  ext4: fix out-of-date comments in extents.c
  ext4: use s_csum_seed instead of i_csum_seed for xattr block
  ext4: use proper csum calculation in ext4_rename
  ext4: fix overhead calculation used by ext4_statfs()
  ...

Merge branch 'for-linus' of git://git.linaro.org/people/rmk/linux-arm

Pull ARM updates from Russell King:
 "First ARM push of this merge window, post me coming back from holiday.
  This is what has been in linux-next for the last few weeks.  Not much
  to say which isn't described by the commit summaries."

* 'for-linus' of git://git.linaro.org/people/rmk/linux-arm: (32 commits)
  ARM: 7463/1: topology: Update cpu_power according to DT information
  ARM: 7462/1: topology: factorize the update of sibling masks
  ARM: 7461/1: topology: Add arch_scale_freq_power function
  ARM: 7456/1: ptrace: provide separate functions for tracing syscall {entry,exit}
  ARM: 7455/1: audit: move syscall auditing until after ptrace SIGTRAP handling
  ARM: 7454/1: entry: don't bother with syscall tracing on ret_from_fork path
  ARM: 7453/1: audit: only allow syscall auditing for pure EABI userspace
  ARM: 7452/1: delay: allow timer-based delay implementation to be selected
  ARM: 7451/1: arch timer: implement read_current_timer and get_cycles
  ARM: 7450/1: dcache: select DCACHE_WORD_ACCESS for little-endian ARMv6+ CPUs
  ARM: 7449/1: use generic strnlen_user and strncpy_from_user functions
  ARM: 7448/1: perf: remove arm_perf_pmu_ids global enumeration
  ARM: 7447/1: rwlocks: remove unused branch labels from trylock routines
  ARM: 7446/1: spinlock: use ticket algorithm for ARMv6+ locking implementation
  ARM: 7445/1: mm: update CONTEXTIDR register to contain PID of current process
  ARM: 7444/1: kernel: add arch-timer C3STOP feature
  ARM: 7460/1: remove asm/locks.h
  ARM: 7439/1: head.S: simplify initial page table mapping
  ARM: 7437/1: zImage: Allow DTB command line concatenation with ATAG_CMDLINE
  ARM: 7436/1: Do not map the vectors page as write-through on UP systems
  ...

Merge branches 'audit', 'delay', 'fixes', 'misc' and 'sta2x11' into for-linus

Merge branch 'for-davem' of git://git./linux/kernel/git/linville/wireless

John W. Linville says:

====================
These fixes are intended for the 3.6 stream.

Hauke Mehrtens provides a pair of bcma fixes, one to fix a build
regression on mips and another to correct a pair of missing iounmap
calls.

Thomas Huehn offers a mac80211_hwsim fix to avoid a possible
use-after-free bug.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

tcp: perform DMA to userspace only if there is a task waiting for it

Back in 2006, commit 1a2449a87b ("[I/OAT]: TCP recv offload to I/OAT")
added support for receive offloading to IOAT dma engine if available.

The code in tcp_rcv_established() tries to perform early DMA copy if
applicable. It however does so without checking whether the userspace
task is actually expecting the data in the buffer.

This is not a problem under normal circumstances, but there is a corner
case where this doesn't work -- and that's when MSG_TRUNC flag to
recvmsg() is used.

If the IOAT dma engine is not used, the code properly checks whether
there is a valid ucopy.task and the socket is owned by userspace, but
misses the check in the dmaengine case.

This problem can be observed in real trivially -- for example 'tbench' is a
good reproducer, as it makes a heavy use of MSG_TRUNC. On systems utilizing
IOAT, you will soon find tbench waiting indefinitely in sk_wait_data(), as they
have been already early-copied in tcp_rcv_established() using dma engine.

This patch introduces the same check we are performing in the simple
iovec copy case to the IOAT case as well. It fixes the indefinite
recvmsg(MSG_TRUNC) hangs.

Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>

Revert "openvswitch: potential NULL deref in sample()"

This reverts commit 5b3e7e6cb5771bedda51cdb6f715d1da8cd9e644.

The problem that the original commit was attempting to fix can
never happen in practice because validation is done one a per-flow
basis rather than a per-packet basis.  Adding additional checks at
runtime is unnecessary and inconsistent with the rest of the code.

CC: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jesse Gross <jesse@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ipv4: fix TCP early demux

commit 92101b3b2e317 (ipv4: Prepare for change of rt->rt_iif encoding.)
invalidated TCP early demux, because rx_dst_ifindex is not properly
initialized and checked.

Also remove the use of inet_iif(skb) in favor or skb->skb_iif

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: fix rtnetlink IFF_PROMISC and IFF_ALLMULTI handling

When device flags are set using rtnetlink, IFF_PROMISC and IFF_ALLMULTI
flags are handled specially. Function dev_change_flags sets IFF_PROMISC and
IFF_ALLMULTI bits in dev->gflags according to the passed value but
do_setlink passes a result of rtnl_dev_combine_flags which takes those bits
from dev->flags.

This can be easily trigerred by doing:

tcpdump -i eth0 &
ip l s up eth0

ip sets IFF_UP flag in ifi_flags and ifi_change, which is combined with
IFF_PROMISC by rtnl_dev_combine_flags, causing __dev_change_flags to set
IFF_PROMISC in gflags.

Reported-by: Max Matveev <makc@redhat.com>
Signed-off-by: Jiri Benc <jbenc@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

USB: kaweth.c: use GFP_ATOMIC under spin_lock

The problem is that we call this with a spin lock held.  The call tree
is:
kaweth_start_xmit() holds kaweth->device_lock.
-> kaweth_async_set_rx_mode()
   -> kaweth_control()
      -> kaweth_internal_control_msg()

The kaweth_internal_control_msg() function is only called from
kaweth_control() which used GFP_ATOMIC for its allocations.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

tcp: Add TCP_USER_TIMEOUT negative value check

TCP_USER_TIMEOUT is a TCP level socket option that takes an unsigned int. But
patch "tcp: Add TCP_USER_TIMEOUT socket option"(dca43c75) didn't check the negative
values. If a user assign -1 to it, the socket will set successfully and wait
for 4294967295 miliseconds. This patch add a negative value check to avoid
this issue.

Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Merge tag 'tty-3.6-rc1' of git://git./linux/kernel/git/gregkh/tty

Pull TTY/Serial patches from Greg Kroah-Hartman:
 "Here's the "tiny" set of patches for 3.6-rc1 for the tty layer and
  serial drivers.  They were cherry-picked from the tty-next branch of
  the tty git tree, as they are small and "obvious" fixes.  The larger
  changes, as mentioned before, will be saved for the 3.7-rc1 merge
  window.

  All of these changes have been in the linux-next releases for quite a
  while.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"
* tag 'tty-3.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  pch_uart: Fix parity setting issue
  pch_uart: Fix rx error interrupt setting issue
  pch_uart: Fix missing break for 16 byte fifo
  tty ldisc: Close/Reopen race prevention should check the proper flag
  pch_uart: Add eg20t_port lock field, avoid recursive spinlocks
  vt: fix race in vt_waitactive()
  serial/of-serial: Add LPC3220 standard UART compatible string
  serial/8250: Add LPC3220 standard UART type
  serial_core: Update buffer overrun statistics.
  serial: samsung: Fixed wrong comparison for baudclk_rate

Merge branch 'kmap_atomic' of git://github.com/congwang/linux

Pull final kmap_atomic cleanups from Cong Wang:
 "This should be the final round of cleanup, as the definitions of enum
  km_type finally get removed from the whole tree.  The patches have
  been in linux-next for a long time."

* 'kmap_atomic' of git://github.com/congwang/linux:
  pipe: remove KM_USER0 from comments
  vmalloc: remove KM_USER0 from comments
  feature-removal-schedule.txt: remove kmap_atomic(page, km_type)
  tile: remove km_type definitions
  um: remove km_type definitions
  asm-generic: remove km_type definitions
  avr32: remove km_type definitions
  frv: remove km_type definitions
  powerpc: remove km_type definitions
  arm: remove km_type definitions
  highmem: remove the deprecated form of kmap_atomic
  tile: remove usage of enum km_type
  frv: remove the second parameter of kmap_atomic_primary()
  jbd2: remove the second argument of kmap_atomic

Merge branch 'merge' of git://git./linux/kernel/git/benh/powerpc

Pull powerpc fixes from Benjamin Herrenschmidt:
 "Here's a handful of powerpc patches, a couple of regression fixes for
  problems introduced in the main batch in this merge window, a couple
  of defconfig updates, and some trivials.

  The radeonfb one is something that was long standing in SLES which I
  forgot to pickup earlier."

* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
  powerpc/ftrace: Trace function graph entry before updating index
  radeonfb: Add quirk for the graphics adapter in some JSxx
  powerpc: Lack of firmware flash support is not an error
  powerpc: Enable pseries hardware RNG and crypto modules
  powerpc: Update g5_defconfig
  powerpc/kvm/bookehv: Fix build regression
  powerpc: Set stack limit properly in crit_transfer_to_handler

Merge tag 'cpumask-for-linus' of git://git./linux/kernel/git/rusty/linux-2.6-for-linus

Pull cpumask changes from Rusty Russell:
 "Trivial comment changes to cpumask code.  I guess it's getting boring."

Boring is good.

* tag 'cpumask-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus:
  cpumask: cpulist_parse() comments correction
  init: add comments to keep initcall-names in sync with initcall levels
  cpumask: add a few comments of cpumask functions